<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <div id="app">
    <h3 v-if='show'>显示if</h3>
    <h3 v-show="show">显示show</h3>
  </div>
  <script src="../js/vue.js"></script>
  <script>
    const app = new Vue({
      el: '#app',
      data: {
        show: true,
        age: 18
      }
    })
  </script>
</body>
</html>